The Drug Enforcement Administration said the investigation, dubbed Operation Raw Deal, was assisted by governments of nine other countries, including China.

In the U.S., agents seized 56 labs that manufactured anabolic steroids and human growth hormone, the DEA said. Agents seized 11.4 million doses of drugs in all.

The seizures and arrests follow a growing number of scandals in the sports world over steroid abuse, but federal authorities in Rhode Island said no professional athletes were directly involved in the investigation.

DEA spokesman Michael Sanders said 143 federal search warrants were issued during the 18-month investigation, many of them since Thursday. The Internal Revenue Service, U.S. Immigration and Customs Enforcement and the Food and Drug Administration were also involved.

In Connecticut, four men were charged with purchasing raw steroid powder from China, manufacturing anabolic steroids in home laboratories and distributed them to customers through a MySpace.com profile and a Web site.

A Chinese corporation and its chief executive were indicted in Rhode Island on federal charges of smuggling illegal human growth hormone into the country in connection with the operation.

"China really stepped up to the plate to help us in this investigation," DEA spokesman Garrison Courtney said in Washington.

The federal grand jury in Rhode Island indicted Genescience Pharmaceutical Co. and its CEO, Lei Jin, last week on charges including money laundering and conspiracy to facilitate the sale of smuggled goods. Lin is accused of marketing the drugs, under the brand name Jinotropin, through e-mail and Web sites.

"Even though their storefront is the Internet, rather than the street corner, the people who engage in the smuggling and distribution of these substances are drug dealers, plain and simple, and we will treat them accordingly," U.S. Attorney Robert Clark Corrente said.

In all, investigators seized over 500 pounds of raw ingredients for steroid manufacture that originated in China.

Other countries participating in the investigation were Mexico, Canada, Australia, Belgium, Denmark, Germany, Sweden and Thailand.

Police in Denmark raided 26 locations across the country. Germany's Federal Criminal office said its agents closed five illicit labs and confiscated tens of thousands of illicit tablets and capsules as part of searches carried out in five of the nation's 16 states.